Re: Digital switch over query

The message <1238331947_5205@xxxxx>
from J G Miller <miller@xxxxxxxx> contains these words:

On Sun, 29 Mar 2009 00:58:01 +0000, Johnny B Good wrote:
> I'm not sure, but it seems you're using router as a synonym for
> ethernet switch(ing hub).

No, I am not, and there is no such thing as a switching hub -- either
a box is a hub or a box is a switch and there is a difference between
them. On a switch, only traffic with the destination IP address of
a specific port is seen by that port, whereas in the case of a hub,
the port sees all the traffic on the local (sub)net. Thankfully,
hubs have pretty much disappeared.

That's a little pedantic regarding _my_ use of the phrase "switch(ing
hub)". I was merely making it clearer as to the function of an "Ethernet
Switch" as being an "Intelligent Hub" (another alternative description
seen on the packaging of small 5 and 8 port SoHo switches).

An ethernet switch substitutes for a (dumb) hub in the cabling schema
of UTP connected network devices (Star topology) removing the
counter-productive re-broadcasting of all packets to every device on the
local subnet. I too am rather glad the (dumb) hub has gone the way of
the Dodo to make way for "intelligent hubs" (aka the ethernet switch).

However, I don't think I explained why you wouldn't need to upgrade a
SoHo router (or modem/router) to gigabit speed when the benefit would
only apply to the lan itself and therefore only require that a gigabit
switch be installed with just one port on the gateway router or
modem/gateway router connected to a port on the gigabit switch. Any
internet bound traffic through the gateway router being limited to the
speed of the internet link (a mere 25Mbps, if you're lucky, on an ADSL2+
line - perhaps 20 or 50Mbps on a cable modem link).

The time to consider the need for a gigabit capable router on a SoHo
setup is when the cable operators start offering 100Mbps and faster
internet service. Whilst it may only be another 2 or 3 years before VM
add the 100Mbps service to their standard range as a premium service, it
may take another 6 or 7 before it loses such status and becomes the
normal, affordable, replacement to the current 10Mbps service now being
supplied to cable served customers.

By the time we reach that stage of development, the gigabit gateway
router will be at the same pricepoint as the current crop of 100Mbps
routers and the lan will be served by a 10Gbit ethernet switch (probably
with fibre optic ports as well as a "Courtesy Gbit ethernet port" for
linking to 'Legacy Devices'). IOW, there's no real need to upgrade the
built in switch on a modem/router to gigabit speeds when a seperate Gbit
switch will provide the solution to boosting the LAN speed. No doubt
that we will eventually see such Gbit modem/router kit, but only when
"The Whole World And Their Dog" are using Gbit LANs as a matter of
routine.


> If a jumbo enabled gigabit device connects to a non jumbo capable
> device, the (intelligent) gigabit switch will repackage the data packets
> appropriately and the connection will proceed at the slower speed
> imposed by the constraints of an MTU value of 1500 or less

Well it is good to hear that this issue has been resolved, but when
home gigabit network devices first came on the market, there was an
issue concerning this matter.

> FreeNAS is based on OpenBSD rather than a Linux distro, but these two
> branches of the Unix family are quite closely related.

For security you cannot do better than OpenBSD.

I'll take your word for that. I wouldn't be surprised if that's
actually true.

I am not sure why you have decided to try Ubuntu rather than Debian
its-self,
the latest version Etch only just having been released last month.

Well, after waiting a couple of hours for the first test install to
complete, I'm not sure either! What's worse, it screwed something in the
boot process on the pen drive install so that it won't actually boot
from said pen drive. However, I can see that I could use a 1GB drive in
place of the 2GB one I tested with.

The second test install, using a 2GB SD card in a card reader is
currently stalled on the "Scanning Disks" phase (over an hour into the
install process). What's really annoying is that the installer looks
nothing special (looking remarkebly as bland and inscrutable as a normal
Debian install, i.e Not very helpful). IOW I can't see any benefit in
going the Ubuntu server route over the bog standard Debian one. I might
as well look on the Debian site and try their latest and greatest
offering.

You've got to hand it to the FreeNAS crew for making a neat and slick
installer which "just works". Not only that, but it installs to a 64MB
(or larger) pen drive or "flash card in a reader" without any trouble
(and, once so installed, can be upgraded through the web interface).

I haven't actually looked on the FreeNAS site for later versions yet. I
was keen to burn the Ubuntu installer CD to try it on a test box to see
whether there was any truth in the claim that it was twice as fast as
FreeNAS on writing files.

> That link has provided me with some interesting stuff to do over the
> next few days... I might be gone for some time. ;-)

Yes, it is a very informative and useful site. I always encourage people
who are looking to upgrade their networking to have a look at the reviews
to dissuade them from just buying blindly at the supermarket/PC store.

Yes, an interesting site. At first glance at the NAS section, I got the
impression they were only pushing the commercial stuff until I stumbled
onto their DIY articles and spotted the FreeNAS / Ubuntu tests on an
Intel Atom MoBo based box.

Ah well, it looks like that Ubuntu install has locked up over the 1KB
sector size issue on the SD card. I guess I'll have to hook up a 'real'
hard drive to the test box and try it again. I'd prefer _not_ to waste
an IDE or SATA port on the boot device if I can help it (perhaps a small
laptop drive connected via the USB would do the job - I can always sort
out a solid state solution later, if the results warrant it).

--
Regards, John.

Please remove the "ohggcyht" before replying.
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